Superposter behavior in MOOC forums

Superposter Behavior
in MOOC Forums
Jonathan Huang
Stanford
Anirban Dasgupta
Yahoo! Labs
Jane Manning
Stanford
Arpita Ghosh
Cornell
Marc Sanders
Stanford
ACM’s Learning @ Scale,
Atlanta, GA
March 4-5, 2014
10 TAsTAs (???)
2,500
Stanford ML-class
Benefits of asynchronous online
discussions
Scaffolding for learners
e.g., Wood et al., ’76, Zhu, ‘96
Benefits for motivation, social
presence, belonging
e.g., Rourke et al., ‘07, Walton et al., ‘12
Gains in learning outcomes
e.g., Schellens and Valcke, ‘06
MOOC forums
Large scale roster, small scale staff =>
distributed, asynchronous means of
communication
Scale is an advantage: chances are better
that someone out there will know the answer!
“…a key ingredient in the success of db-class
was Amy Cunningham. Amy answered almost
900 questions on the Q&A Forum -- each one
patiently, correctly, and at just the right level of
detail. I couldn't have done a better job
myself.”
Amy Cunningham went on to
become a superposter in a number of
“What's truly amazing about this new medium is
other
afterwards…
that while
AmyMOOCs
was helping
herself learn, she
was a tremendous (some might say
indispensable!) resource to tens of thousands of
others at the same time.”
# forum participants
The ubiquitous heavy tail
Few
contributions
Many, many
contributions
e.g., Wilkinson, ‘08, Wu et al., ‘09
Superposters: The good…
(not to be confused
with Superman posters)
Support staff in answering questions
Start conversations
Contribute to “critical mass” of
forum participation
Inspire peers by example
the bad…
Can superposting behavior lead to a
“chilling effect” on MOOC forums?
and the ugly!
“Someone can't handle the truth.”
“English is a civilized language. Not Hindi.”
“I will predict in advance that the Diamond's
analysis of the US will be about 99.9% wrong.”
“You don't know much about history. The US has
done more to promote democracy than any
other country in the history of the world. Ever. That
ain't bragging. It's fact.”
Should we encourage
superposters?
What things are characteristic of
superposters?
Highly engaged?
High scoring?
Course
designers,
Do superposters
create
value on
pay
attention!!
forums?
Hopefully!
Do superposters suppress forum
activity of others?
Hopefully Not.
Anatomy of a thread
Option to “subscribe” to thread
Post #1
Comments (optionally)
attached to posts
Option to vote (up or down) for post
Post #2
44
# MOOC offerings
Writing in the
70,419
Total # threads
Sciences
325,071
Non-STEM Total # contributions
~91,000Total
enrolled
# unique contributors
Child Nutrition 116,028
1432 threads
Non-STEM
Median # registered students
per course 40,674
3607 forum participants
~32,000 enrolled
2181
Median # unique contributors
per course
1183 threads
1959course
forum participants1,297
Median # threads per
Algorithms
Compilers
STEM
Algorithms
Probabilistic
Graphical Models
~44,500 enrolled
Game
1233Theory
threads
Automata
2305
forum participants
Child
Nutrition
Understanding Einstein: The
Special Theory of Relativity
CS101
Design
Human Computer Interaction
Machine Learning
Mathematical Thinking
Gamification
Organizational
Analysis
STEM
Crytography
~33,500 enrolled
Writing in the Sciences
1021
threads
World
Music
Democratic
Development
2665 forum
participants
Introduction to Logic
Intro to Logic
Caveat Emptor: Data collected in wild!
Draw causal conclusions at your own risk!
Superposters Characterizations
Quantity Superposters
Top 5% in course w.r.t. average number
contributions per week
Quality Superposters
Top 5% in course w.r.t. ratio of user’s #
votes to average # votes for other users
in thread (averaged over threads)
Reputation Superposters
Top 5% in course w.r.t. sum of square
roots of votes across all contributions
Superposterhood
Value creation
Relationship with
overall forum activity
Superposter Demographics
See also: https://signalblog.stanford.edu/forumdemographics/
Fraction of posters
0.3
0.25
0.2
0.15
0.1
0.05
0
Age
Superposters
Non-Superposters
Superposters take more courses
1
Frequency (proportional to #
students)
1
2
3
4
5
6
7
8
0.1
0.01
0.001
All Posters
0.0001
Superposters by Quantity
Superposters by Reputation
Superposters by Quality
0.00001
Number of classes registered
9
10
Cross-course forum behavior
~116,000 total forum participants
~8000 forum participants enrolled in >1 courses
~6200 forum participants enrolled in 2 courses
Non-SP in
SP in
Course #2 Course #2
Non-SP in Course #1
5328
386
SP in Course #1
386
128
Students > 3X more likely to be SP in
both courses than expected if SPness
was independent across courses
χ2 = 205.34, p ≤ .01
# grade standard
deviations
Superposters outscore peers
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
Quantity SPs outscored other forum
posters by ~1.3 standard deviations
Quantity Reputation Quality
** To control for time of engagement, only considered
students who watched > 90% lectures for a course.
Grade disparity is
subject dependent
3
2.5
2
1.5
1
0.5
0
Logic Superposters significantly
outperform other forum
participants!
maththink-002
maththink-…
compilers-003
compilers
compilers-…
pgm
pgm-003
pgm-2012-002
ml
ml-2012-002
intrologic-…
intrologic
intrologic-003
algo-2012-002
algo
algo-003
crypto-005
crypto-2012-002
crypto-2012-003
crypto-006
crypto
hci-003
hci-2012-002
gametheory
gametheory-…
# grade standard
deviations
ML Superposters don’t outperform
other forum participants by much
Courses that were run more than once
** footnote: baseline is average grade of forum participants, not average
grade of all students
Superposterhood
Value creation
Relationship with
overall forum activity
Up close and personal
Intro to Logic; Superposter #1; 251 posts
“You're in good shape at line 26, but then you
go off on a bit of a tangent. For line 27, try
assuming ~(~p | ~q) instead in order to prove
~(~p | ~q) => ~(p & q) for your contradiction…”
“You're really exactly where you want to be
Rowena (you just have p and q flipped from the
way I did it, which may be why you're not seeing
the hint)… …So you can do two assumptions of
q and use reiteration… …and the rest of the
proof will collapse down to your conclusion in
short order.”
** names have been changed to protect the innocent
Up close and personal
Algorithms; Superposter #2; 127 posts
“sorry I don't get this. The arcs are predetermined at the beginning. If an arc is set to
go forward, it doesn't matter what algorithm
you use, it still goes forward… …What have I got
wrong?”
“…A little smarter is always better. Learning is
always a fun journey.”
“…Thanks to all the people who post the test
cases… …thanks to all the programmer gurus
who are willing to help out people in the cloud
and make this online course possible as well as
enjoyable.”
# posts
% on-content
from top 3
posts from
SPs
top 3 SPs
Superposters… 521
Child Nutrition
81%
give more than they receive…
Algorithms
380
80%
and get fewer downvotes…
551posts… 79%
and tend to write longer
Intro to Logic
Writing
the
544 threads…
39%
and in
respond
earlier within
Sciences
** see stores (paper) for details
Content from superposters models the
behavior we hope to see in any study
group, whether online or in-person.
Superposterhood
Value creation
Relationship with
overall forum activity
Non superposter
contributions per active
student in course
No suppression of activity from
others: more posts
1.4
1.2
1
R² = 0.6658
0.8
0.6
0.4
0.2
0
0
0.2
0.4
0.6
0.8
Superposter contributions per active
student in course
** Active students = students who watched > 5%
lectures for a course.
Non-superposter threads
initiated per active student
in course
No suppression of activity from
others: more threads initiated
0.18
0.16
0.14
0.12
R² = 0.5319
0.1
0.08
0.06
0.04
0.02
0
0
0.2
0.4
0.6
0.8
Superposter responses per active
student in course
Number of upvotes per
active student in course
No suppression of activity from
others: more votes received
0.8
0.7
0.6
R² = 0.4985
0.5
0.4
0.3
0.2
0.1
0
0
0.2
0.4
0.6
Superposter responses per active
student in course
Takeaways
SPs exhibit high engagement, performance
SP-hood is to some extent an inherent trait
SPs respond faster, write longer posts, are
less likely to be down-voted, generally
contribute on-content posts
SPs do not suppress activity by other posters
Thank You!